1,2,3,4-di-O-isopropylidene-α-D-galactooct-6-enopyrannuronate d'ethyle 、
肌氨酸 、
靛红 以
甲苯 为溶剂,
反应 4.5h,
以86%的产率得到ethyl (3R,3'S,4'R)-1'-methyl-2-oxo-4'-[(1S,2R,6R,8R,9S)-4,4,11,11-tetramethyl-3,5,7,10,12-pentaoxatricyclo[7.3.0.02,6]dodecan-8-yl]spiro[1H-indole-3,2'-pyrrolidine]-3'-carboxylate